Methods for protecting and treating traumatic brain injury, concussion and brain inflammation with intranasal insulin

ABSTRACT

The present system is directed in several embodiments to a method of administration of a therapeutic composition for protection of the brain of a subject at risk of injury leading to traumatic brain injury (TBI) and/or treatment of injury to the brain resulting from TBI. The method includes administering one or more therapeutic compositions comprising an effective amount of insulin directly to the subject patient&#39;s CNS, with no to minimal systemic exposure. Preferably, this method comprises administration of an effective amount of insulin to the upper third of a patient&#39;s nasal cavity, thereby bypassing the patient&#39;s blood-brain barrier and delivering the therapeutic composition directly to the patient&#39;s central nervous system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 14/679,667,filed Apr. 6, 2015 and entitled “Methods for Protecting and TreatingTraumatic Brain Injury, concussion and Brain Inflammation withIntranasal Insulin” and also claims priority to App. Ser. No.61/976,634, entitled “Method of Treating and/or Preventing Injury to theBrain Caused by Traumatic Brain Injury by Intranasal Administration ofInsulin,” filed Apr. 8, 2014, the entire contents of which are herebyincorporated by reference in their entirety.

FEDERAL FUNDING

None

BACKGROUND OF THE INVENTION Field of the Invention

The present invention is directed to methods of protection of the brainof a subject at risk of injury leading to traumatic brain injury (TBI)and/or treating injury to the brain in patients with TBI. Moreparticularly, the present disclosure is directed to a method ofprotection of the brain of a subject at risk of injury leading to TBIand/or treating TBI by administration of an effective amount of insulinto the upper third of the patient's nasal cavity.

Description of the Related Art

Traumatic Brain Injury (TBI) occurs when sudden trauma causes damage tothe patient's brain, e.g., when the head is suddenly and violently hitby an object or when an object pierces the skull and enters thepatient's brain tissue.

The most common causes and risk activities for TBI include falls,vehicle crashes and sports injuries. Indirect forces that jolt the brainviolently within the skull, e.g., shock waves from a battlefieldexplosion also may result in TBI as may bullet wounds or otherbrain-penetrating injuries.

Symptoms of a TBI include unconsciousness, inability to recall thetraumatic event, confusion, headache—including a headache that will notgo away or worsens with time, lightheadedness, dizziness, blurred visionor tired eyes, ringing in the ears, bad taste in the mouth, fatigue,lethargy, a change in sleep patterns, behavioral or mood changes,trouble with memory, concentration, attention or thinking, repeatedvomiting, nausea, convulsions, seizures, an inability to awaken fromsleep, dilation of one or both pupils of the eyes, trouble speakingcoherently—including slurring of speech, weakness or numbness in theextremities, unsteadiness, lack of coordination, restlessness andagitation.

TBI is a threat to an individual's health in at least the followingways:

-   -   (1) TBI has direct effects, a short listing of these are        provided above;    -   (2) Certain TBI's may increase the risk of developing        Alzheimer's disease and certain forms of dementia; and    -   (3) Repeated TBI, such as those that can occur in contact sports        such as football, boxing, hockey, lacrosse and soccer to name a        few, may be linked to an increased risk of a dementia known as        chronic traumatic encephalopathy.

As defined herein, TBI, in addition to the above, includes concussioninjuries; concussions being a type of TBI.

Thus, patients at risk, as referred to herein, may comprise individualsengaged in contact sports who are at risk for head injuries as well asthose individuals in professions, e.g., soldiers, police officers, firefighters, athletes in contact sports and the like, that places them atrisk of head injuries leading to TBI.

So far as we are aware, the only preventive, or protective, treatmentcurrently available includes protective gear such as helmets forpatients at risk of brain injuries that may lead to TBI. Once TBI isdiagnosed, the primary focus and treatment comprises ensuring thepatient's brain is properly oxygenated, with sufficient blood flow andcontrol of blood pressure. More severe cases may require treatmentinvolving physical therapy, occupational therapy, speech and languagetherapy, physical medicine, and psychological and/or psychiatrictherapy.

Delivery of the agent and/or composition to the upper one third of thepatient's nasal cavity is a means of bypassing the BBB to administertherapeutic compounds and/or agents directly to the CNS. Evidence existsthat intranasal treatment with certain therapeutic agent(s) improves,i.e., prevents, protects against and/or treats, a variety ofneurological and psychiatric disorders, e.g., stroke, in animals. Thisbasic methodology is discussed and described in U.S. Pat. No. 5,624,898to Frey II entitled Method for Administering Neurologic Agents to theBrain, as well as in U.S. Pat. No. 6,313,093 to Frey II, the entirecontents of each of which are hereby incorporated by reference. Thisadministration technique is a vast improvement over systemicadministration methods such as intravenous and oral administration ofdrugs which generally cannot cross the BBB to reach their targets withinthe CNS. In addition, Frey's intranasal method is a significantimprovement over the general inhalation methods which target the lowertwo-thirds of the patient's nasal cavity. Both the systemic and generalintranasal method targeting the lower two-thirds of the nasal cavityresult in a very large, unwanted and potentially dangerous systemicexposure to the administered drug or therapeutic agent(s). The presentinvention addresses, inter alia, this general intranasal problem as wellas ensures that the patient's non-CNS, systemic disease and/or conditionis protected from exposure to the therapeutic agent administered to theupper third of the nasal cavity, and potential harm therefrom.

General inhalation methods to the lower two-thirds of the nasal cavitydelivered by, e.g., nasal spray bottles, on the other hand, result in alarge amount of systemic absorption and exposure, with a very smallamount of the administered compound, i.e., less than 5%, making thetortuous journey around the turbinates to the upper third of the nasalcavity and still less compound than that very small amount furtherbypassing the BBB to actually reach the CNS.

Delivery and administration to the upper third of the nasal cavity, isvery effective in administering the subject compounds or agents to thedesired target, i.e., the CNS, without significant systemic exposure,though some systemic exposure does occur as is further discussed below.

Unwanted systemic exposure of therapeutics used to treat CNS diseasescreate several serious problems. The systemic metabolism greatly reducesthe bioavailability of any agent and/or compound exposed to the non-CNSsystem. This reduction of bioavailability is increased by unwantedplasma protein binding of the agent and/or compound. As a result, only asmall amount of the active therapeutic agent and/or compound actuallyreaches the CNS. Because of these, inter alia, issues, the actual dosethat must be administered in order to achieve a therapeutic dose in thetargeted CNS is far larger than the therapeutic dosing. As aconsequence, a relatively large concentration of the agent(s) and/orcompounds(s) is in the system and will affect non-target systemic organsand systems. This can create unwanted and often dangerous side effectson these non-target organs and systems, particularly in the specificcase of patient's having a systemic, non-CNS disorder or condition thatcontraindicates the systemic use or exposure of the therapeutic agent(s)needed to treat a CNS-related disorder or condition.

We have addressed the efficiency needs in patent application Ser. No.12/134,385 to Frey II, et al., entitled “Pharmaceutical Compositions andMethods for Enhancing Targeting of Therapeutic Compounds to the CentralNervous System, the entire contents of which are hereby incorporated byreference, and wherein a vasoconstrictor is administered to thepatient's nasal cavity either just prior to, or in combination with,administration of at least one therapeutic agent and/or pharmaceuticalcomposition(s) comprising a therapeutic compound(s) and/or agent(s). Theefficiency of the direct administration of the pharmaceutical compoundto the CNS, with concomitant reduction of systemic exposure of thepharmaceutical compound is remarkable.

Moreover, we provide disclosure of the following patents andapplications, each of which are commonly assigned with the presentapplication and incorporated herein in their entirety for disclosure of,inter alia, the various diseases, conditions or disorders of the CNSrelating herein to the first disease or condition of the presentinvention, as well as various compounds and/or therapeutic agents fortreating same by application to the upper ⅓ of the nasal cavity,bypassing of the blood-brain barrier and subsequent direct delivery ofthe compounds and/or agents to the CNS:

U.S. Pat. No. 7,972,595 Methods and compositions for protecting andtreating at least one muscarinic receptor from dysfunction not resultingfrom oxidative stress, toxic actions of metals or infectious agents byadministering a pyrophosphate analog;

U.S. Pat. No. 7,786,166 Methods and compositions for protecting andtreating muscarinic receptors through administration of at least oneprotective agent;

U.S. Pat. No. 7,776,312 Method of treating Alzheimer's diseasecomprising administering deferoxamine (DFO) to the upper one-third ofthe nasal cavity;

U.S. Pat. No. 7,618,615 Methods for providing neuroprotection for theanimal central nervous system against neurodegeneration caused byischemia;

U.S. Pat. No. 7,084,126 Methods and compositions for enhancing cellularfunction through protection of tissue components;

U.S. Pat. No. 6,313,093 Method for Administering Insulin to the Brain;

US Pat Application 20100061959 Methods for Providing Neuroprotecton forthe Animal Central Nervous System Against the Effects of lschemia,Neurodegeneration, Trauma, and Metal Poisoning;

US Patent Application 20080305077 Pharmaceutical Compositions and Methodfor Enhancing Targeting of Therapeutic Compounds to the Central NervousSystem;

US Patent Application 20110311654 Methods and PharmaceuticalCompositions for Treating the Animal Central Nervous System forPsychiatric Disorders;

US Patent Application 20110236365 Method for Protecting and Treating atLeast One Muscarinic Receptor From Dysfunction Resulting From FreeRadical Damage.

The use of therapeutic agents or compounds that are being used to treatcentral nervous system (CNS)-related conditions or diseases or disorderssuch as traumatic brain injury (TBI) may cause unnecessary, unwanted andpotentially adverse side effects when given systemically or by generalinhalation methods to the lower two-thirds of the patient's nasalcavity. In part, this may occur because systemic uptake dictates that amuch larger dose be given, e.g., orally or intravenously, in order toensure that an effective dose actually crosses the blood-brain barrierand enters the CNS. For example, gastric problems including GI upset,negative effects on blood pressure, and/or cardiac, liver, or kidneytoxicity may result from systemic administration. Accordingly, a needexists for a therapeutic agent or compound that may be used to protectthe brain of patients potentially at risk of events that place thepatients at risk of developing TBI. Further, a need exists for atherapeutic agent or compound that may be used to treat TBI. Further, aneed exists for such a therapeutic agent or compound that minimizes theadverse side effects generally associated with administration of drugsused to treat CNS-related disorders. Still further, a need exists for adelivery system for such a composition that provides for enhanced uptakeof the composition to maximize the therapeutic affect obtained peradministration.

The present invention provides solutions for, inter alia, theseproblems.

SUMMARY OF THE INVENTION

The present system is directed in one embodiment to a method ofadministration of a therapeutic composition for protecting the brain ofa subject at risk of suffering an injury leading to traumatic braininjury and/or treatment of injury to the brain resulting from traumaticbrain injury. The method includes administering one or more therapeuticcompositions comprising an effective amount of insulin directly to thesubject patient's CNS, with no to minimal systemic exposure. Preferably,this method comprises administration to the upper third of a patient'snasal cavity, thereby bypassing the patient's blood-brain barrier anddelivering the therapeutic composition directly to the patient's centralnervous system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a bar graph indicating time for vehicle subjects compared withinsulin subjects to traverse beam walk;

FIG. 2 is a bar graph indicating time for vehicle subjects compared withinsulin subjects to traverse the peg walk;

FIG. 3 is a bar graph indicating expression of CD206 in vehicle subjectscompared with insulin subjects;

FIG. 4 is a bar graph indicating expression of CD86 in vehicle subjectscompared with insulin subjects;

FIG. 5 is a line graph indicating a lack of change in blood glucoseafter intranasal insulin delivery (injury− CCI− completed at time=1 h;insulin or saline administered at time=4 h; final blood draw at time=7h);

FIG. 6 is a bar graph indicating number of target island crosses forvehicle subjects compared with insulin subjects in Morris water mazeprobe trial;

FIG. 7 is a bar graph indicating search strategy analysis for vehiclesubjects compared with insulin subjects in Morris water maze probetrial;

FIG. 8a is a line graph illustrating neuronal viability in the salinerat hippocampus; and

FIG. 8b is a line graph illustrating improved neuronal viability in theinsulin rat hippocampus compared with the saline rat hippocampus.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used herein, “central nervous system” (CNS) refers to the brain andspinal cord and associated cells and tissues.

As used herein, “systemic administration” refers to administration of amedication, pharmaceutical and the like by the following non-limitedmeans: oral, intravenous, intra-arterial, intramuscular, epidermal,transdermal, subcutaneous, topic, sublingual as well as generalinhalation, i.e., administration to the lower two-thirds of thepatient's nasal cavity. In each of these cases, the administered drugwill migrate through the patient's circulatory system and, in order toreach the patient's CNS would be required to cross the patient'sblood-brain barrier.

In the context of the present invention, the terms “treat” and “therapy”and the like refer to alleviate, slow the progression, prophylaxis,attenuation or cure of existing disease or condition that has or iscausing cell death in the CNS.

“Protect”, as used herein, refers to putting off, delaying, slowing,inhibiting, or otherwise stopping, reducing or ameliorating the onset oftraumatic brain injury (TBI). It is preferred that a large enoughquantity of the therapeutic agent(s) and/or compound(s) be applied innon-toxic levels in order to provide an effective level of activityagainst TBI in subjects, e.g., soldiers, police officers, fire fighters,football players and the like, who are at risk of injury leading to TBIby engaging in violent activities that may lead to head trauma and TBIor related concussive injuries. Consequently, patients or subjectspreparing to engage in such violent activities are at risk of injuryleading to TBI and may, therefore, receive protective effects from thepresent invention if administered before actually engaging in saidviolent activities. Administering an effective amount of insulin to thepatient's brain does, as provided below, reduce inflammation within thebrain. Administering the invention to the at-risk patient or subjectthus provides a higher-than-normal concentration of insulin within thebrain during the course of the violent activity, once actually engagedin by the patient or subject. In turn, this concentration of insulinprovides protection against inflammation incurred as a result of headtrauma, working to reduce the inflammation as soon as it appears. Thisis in contrast with the patient diagnosed with TBI or other concussiveor inflammatory brain condition. The present invention may be used totreat the patient's diagnosed TBI, concussive or inflammatory braincondition.

The method of the present invention may be used with any animal, such asa mammal or a bird (avian), more preferably a mammal. Poultry are apreferred bird. Exemplary mammals include, but are not limited to rats,mice, cats, dogs, horses, cows, sheep, pigs, and more preferably humans.

An “effective amount” of therapeutic agent(s), i.e., insulin, and/orcomponent(s) of the pharmaceutical composition of the present inventioncomprising therapeutic agent(s) is an amount sufficient to protectagainst injury to the brain of a subject at risk of injury leading toTBI, treat, reduce and/or ameliorate the symptoms, neuronal damageand/or underlying causes of TBI. In some instances, an “effectiveamount” may be sufficient to eliminate the symptoms of TBI and overcomethe disease itself. Preferably, at least an effective amount of the atleast one therapeutic agent, i.e., insulin, and/or component(s) of thepharmaceutical composition yields a tissue concentration in the range ofabout 10⁻¹³ molar to about 10⁻⁹ molar, but the concentrations may begreater provided that toxicity is avoided. Generally, at least aneffective amount of insulin or pharmaceutical composition(s) thereof isadministered in order to ensure that an effective amount of insulin isdelivered to the target CNS for protection of the brain of a subject atrisk of injury leading to TBI and treating TBI.

The concentration range of insulin delivered to the upper third of thepatient's nasal cavity may be preferably in the range of 10⁻¹⁰ molar toabout 10⁻⁶ molar in order to yield the preferable tissue concentrationrange of about 10⁻¹³ molar to about 10⁻⁹ molar, though as discussedabove, concentrations in the tissue may be higher so long as toxicity isavoided.

For illustrative purposes only, exemplary treatment regimens relatinggenerally to the therapeutic agent, i.e., insulin, and/or pharmaceuticalcompounds disclosed herein, including dosage ranges, volumes andfrequency are provided below:

Efficacious dosage range for the at least one therapeutic agent, i.e.,insulin and/or vasoconstrictors comprises 1×10⁻⁷ to 0.1 mg/kg.

A more preferred dosage range may be 1×10⁻⁴ to 0.1 mg/kg.

The most preferred dosage range may be 0.01 to 0.1 mg/kg.

The dosage volume (applicable to nasal sprays or drops) range may be0.015 ml-1.0 ml.

The preferred dosage volume (applicable to nasal sprays or drops) rangemay be 0.03 ml-0.6 ml.

The brain concentrations that are likely to be achieved with the dosageranges provided above are for each of the therapeutic agents describedabove, including insulin, for a single dose: 1×10⁻¹³ to 1×10⁻⁹ M.

The present disclosure is generally directed to administering insulinintranasally to patients for treatment and/or protection of the brain ofa subject at risk of injury leading to TBI of traumatic brain injury(TBI).

Generally, the method of the present invention comprises protecting theat-risk brain, or treating TBI with the direct non-invasive delivery ofa therapeutic, i.e., effective, amount or dose of insulin, or apharmaceutical composition thereof, to the CNS. This may be accomplishedby administration of at least an effective or therapeutic amount ofinsulin, or pharmaceutical composition thereof, to the upper one-thirdof the patient's nasal cavity, thereby delivering the effective ortherapeutic amount or dose directly to the patient's CNS, with minimalsystemic exposure.

In some embodiments, the therapeutic agent—insulin—may be combined witha vasoconstrictor to be administered intranasally to limit systemicexposure. The vasoconstrictor may be administered to the nasal cavityprior to administration of the therapeutic compound to the upper third,or alternatively to the lower two-thirds, of the nasal cavity or, stillmore alternatively, the vasoconstrictor and therapeutic compound may beadministered concurrently, either to the upper one-third or the lowertwo-thirds of the patient's nasal cavity. Thus, the present inventionallows for a safe and efficacious treatment, or protection of theat-risk brain, of a patient's TBI where systemic administration orexposure is contraindicated.

While not used in conjunction with the treatment of TBI, administrationof intranasal insulin has been shown to improve memory in both normaladults and in patients with Alzheimer's disease. Recent studies haveshown that insulin may enhance neuronal activity within themedio-temporal lobe and increase performance in humans under in-vivoconditions. Impaired insulin sensitivity may be associated with deficitsin verbal fluency and temporal lobe gray matter volume in the elderly.

There are a variety of types of insulin available that may be used inaccordance with the present disclosure, including insulins for whichzinc is included for stabilization and others which do not include zinc.Because zinc may be detrimental to the olfactory system, insulins thatdo not contain zinc may be preferable in some cases. Formulations ofinsulin that either contain no preservatives (which could be preparedfor unit dosing) or a safe preservative such as pyrophosphate arepreferred. In some embodiments the insulin formulation may not includeany phenol or cresol preservatives.

It is preferred that the neurologic agent—insulin—promote nerve cellgrowth and survival or augment the activity of functioning cells. Theneurologic agent may be administered intranasally as a powder, spray,gel, ointment, infusion, injection, or drops, for example. The insulinmay be administered in an effective dose. The intranasal composition maybe dispensed as a powder or liquid nasal spray, nose drops, a gel orointment, through a tube or catheter, by syringe, by packtail, bypledget, or by submucosal infusion. Any suitable nasal spray device maybe used with embodiments of the present disclosure.

In some embodiments, the composition may include the neurologictherapeutic agent (insulin) as well as a vasoconstrictor that maygenerally enhance the intranasal therapeutic compound targeting the CNS,as is further described in U.S. patent application Ser. No. 12/134,385,entitled, “Pharmaceutical Compositions and Methods for EnhancingTargeting of Therapeutic Compounds to the Central Nervous System,” filedon Jun. 6, 2008, which is hereby incorporated herein in its entirety. Asprovided in the aforementioned application, constriction of bloodvessels resulting from action of the vasoconstrictor in the nasal cavityfacilitates transport of the therapeutic compound(s) or agent(s) intothe brain along olfactory and trigeminal neural pathways, perivascularpathways, or lymphatic pathways. Thus, intranasal delivery of atherapeutic compound(s) or agent(s) in combination with an agent thatconstricts blood vessels (i.e. a vasoconstrictor) within or in theproximity of the mucosa of the nasal cavity enhances intranasal drugtargeting to, inter alia, the CNS by reducing absorption into the blood,increasing CNS concentrations (as well as other targeted locations), orboth.

In one embodiment, the pharmaceutical composition may be comprised of acombination of at least one therapeutic compound comprising insulin andat least one vasoconstrictor. In another embodiment, at least onevasoconstrictor may be applied intranasally or otherwise, i.e.,intravenously, topically as a pretreatment or concurrently withadministration of at least one therapeutic compound.

Inclusion of vasoconstrictors in intranasal formulations that includeinsulin for protection of the brain of a subject at risk of injuryleading to TBI and/or treatment of TBI may include, but are not limitedto providing the following advantages: reducing absorption into theblood, which is desirable for drugs with adverse side effects in theblood or in peripheral tissues; reducing systemic drug exposure, whichis important for drugs that are rapidly eliminated in drug metabolizingorgans or for drugs that are extensively bound to plasma proteins;targeting drugs to the olfactory epithelium for CNS delivery of drugs;reducing clearance of the drug into the blood from the nasal cavity,which increases the residence time and contact with the nasalepithelium; targeting drugs to the olfactory epithelium, olfactory bulbsand/or anterior olfactory nucleus to have therapeutic potential for thetreatment of TBI; targeting high potency drugs to the frontal cortex toreach brain targets involved in cognition disorders, motor dysfunctionin TBI; and targeting the hippocampus for treatment of learning andmemory disorders associated with TBI.

Exemplary vasoconstrictors in the various embodiments of the presentinvention may comprise, without limitation, PHE and/or THZ. Additionalvasoconstrictors will be well known to the skilled artisan and mayinclude, again without limitation, methoxamine, phenylephrine,ephedrine, norepinephrine, oxymatazoline, tetrahydrozoline,xylometazoline, clonidine, guanabenz, guanfacine, α-methyldopa, and/orarginine vasopressin.

An at least an effective amount, as herein defined, of the therapeuticcompound, i.e., insulin, and/or vasoconstrictor to be administeredpursuant to embodiments of the invention is the most preferred method ofexpression of dosage. Such effective amount is dependent upon manyfactors, including but not limited to, the type of disease or conditiongiving rise to an anticipated cerebral ischemia episode, the patient'sgeneral health, size, age, and the nature of the treatment, i.e.short-term or chronic treatment.

Generally, the treatment may be given in a single dose or multipleadministrations, i.e., once, twice, three or more times daily over aperiod of time. In some cases, one or more doses daily may be given overan extended period of time, including, months or years.

The method of the invention administers an at least an effective amountof the insulin, or pharmaceutical compound thereof, to the upper thirdof the nasal cavity of a mammal. It is preferred that the at least aneffective amount of insulin be administered to the olfactory area in theupper third of the nasal cavity and particularly to the olfactoryepithelium in order to promote transport of the agent into theperipheral olfactory neurons rather than the capillaries within therespiratory epithelium. In some embodiments it may be preferable totransport insulin to the brain by means of the nervous system instead ofthe circulatory system so that therapeutic agents that are unable tocross the blood-brain barrier from the bloodstream into the brain may bedelivered to damaged neurons in the brain.

Transportation Pathway to Bypass Blood-Brain Barrier

The Olfactory Nerve

Various methods of the present invention include administration of atleast an effective amount of insulin and/or pharmaceuticalcomposition(s) thereof to tissue innervated by the olfactory nerve andthat is located in the upper third of the nasal cavity. The at least aneffective amount of insulin and/or pharmaceutical composition(s) thereofcan be delivered to the olfactory area via application to the upperthird of the nasal cavity.

Fibers of the olfactory nerve are unmyelinated axons of olfactoryreceptor cells that are located in the upper one-third of the nasalmucosa. The olfactory receptor cells are bipolar neurons with swellingscovered by hair-like cilia that project into the nasal cavity. At theother end, axons from these cells collect into aggregates and enter thecranial cavity at the roof of the nose. Surrounded by a thin tube ofpia, the olfactory nerves cross the subarachnoid space containing CSFand enter the inferior aspects of the olfactory bulbs. Once thetherapeutic agent(s) and/or pharmaceutical composition(s) of the presentinvention is applied to the upper third of nasal cavity, the therapeuticagent(s) and/or pharmaceutical composition(s) of the present inventioncan undergo transport through the nasal mucosa and into the olfactorybulb and other areas of the CNS, such as the anterior olfactory nucleus,frontal cortex, hippocampal formation, amygdaloid nuclei, nucleusbasalis of Meynert, hypothalamus, midbrain, cerebellum, cervical spinalcord and the like.

Neuronal Transport

Embodiments of the present method includes administration of an at leastan effective amount of insulin and/or pharmaceutical composition(s)thereof of the present invention to the subject by application to theupper third of the mammalian subject's nasal cavity. Application of theat least an effective amount of insulin and/or pharmaceuticalcomposition(s) thereof of the present invention in this manner ensuresthat an effective amount of insulin and/or pharmaceutical composition(s)are transported to the CNS, brain, and/or spinal cord along a neuralpathway, with reduced systemic loss and, therefore, minimized systemicexposure. A neural pathway includes transport within or along a neuron,through or by way of lymphatics running with a neuron, through or by wayof a perivascular space of a blood vessel running with a neuron orneural pathway, through or by way of an adventitia of a blood vesselrunning with a neuron or neural pathway, or through an hemangiolymphaticsystem.

The present invention comprises transportation of the administeredinsulin and/or pharmaceutical composition(s) thereof by way of a neuralpathway, rather than through the circulatory system, so that agent(s)and/or compound(s) that are unable to, or only poorly, cross theblood-brain barrier from the bloodstream into the brain can be deliveredto the lymphatic system, CNS, brain, and/or spinal cord. The therapeuticagent(s) and/or pharmaceutical composition(s) of the present invention,once past the blood-brain barrier and in the CNS, can then be deliveredto various areas of the brain or spinal cord through lymphatic channels,through a perivascular space, or transport through or along neurons.

Use of a neural pathway to transport a therapeutic agent(s) and/orpharmaceutical composition(s) to the brain, spinal cord, or othercomponents of the central nervous system obviates the obstacle presentedby the blood-brain barrier so that medications, i.e., therapeuticagent(s) and/or pharmaceutical compositions of the present invention,that cannot normally cross that barrier, can be delivered directly tothe CNS, e.g., the brain and spinal cord. In addition, the presentinvention can provide for delivery of a more concentrated level of thetherapeutic agent(s) and/or pharmaceutical composition(s) of the presentinvention to the CNS since the therapeutic agent(s) and/orpharmaceutical composition(s) of the present invention do not becomediluted in fluids present in the bloodstream. As such, the inventionprovides an improved method for delivering an effective amount ortherapeutic dose of the administered insulin and/or pharmaceuticalcomposition(s) thereof directly to the target CNS including the brainand/or spinal cord.

The Olfactory Neural Pathway

One embodiment of the present method includes delivery of the effectiveamount of insulin to the subject's CNS for protection of the brain of asubject at risk of injury leading to TBI and treatment of TBI in amanner such that the at least an effective amount of insulinadministered to the upper third of the nasal cavity is transported intothe CNS, e.g., the brain, and/or spinal cord along an olfactory neuralpathway. Typically, such an embodiment includes administering the atleast an effective amount of insulin and/or other compound(s) to tissueinnervated by the olfactory nerve and inside the nasal cavity. Theolfactory neural pathway innervates primarily the olfactory epitheliumin the upper third of the nasal cavity, as described above. Applicationof the at least an effective amount of insulin to a tissue innervated bythe olfactory nerve can deliver an effective amount of insulin and/orcompound(s) to damaged neurons or cells of the CNS, including but notlimited to the brain, and/or spinal cord. Olfactory neurons innervatethis tissue and can provide a direct connection to the CNS, brain,and/or spinal cord due, it is believed, to their role in olfaction.

Delivery through the olfactory neural pathway can employ lymphatics thattravel with the olfactory nerve to the various brain areas and fromthere into dural lymphatics associated with portions of the CNS, such asthe spinal cord. Transport along the olfactory nerve can also deliver aneffective amount of insulin and/or compound(s) to an olfactory bulb. Aperivascular pathway and/or a hemangiolymphatic pathway, such aslymphatic channels running within the adventitia of cerebral bloodvessels, can provide an additional mechanism for transport of aneffective amount of insulin, e.g., to the brain and spinal cord fromtissue innervated by the olfactory nerve.

At least an effective amount of insulin, and/or pharmaceuticalcompositions thereof may be administered to the olfactory nerve, forexample, through the olfactory epithelium located at the upper one-thirdof the nasal cavity. Such administration can employ extracellular orintracellular (e.g., transneuronal) anterograde and retrograde transportof the agent(s) and/or compound(s) entering through the olfactory nervesto the brain and its meninges, to the brain stem, or to the spinal cord.Once the at least an effective amount, i.e., therapeutic dose, of theinsulin and/or pharmaceutical composition thereof is dispensed into oronto tissue innervated by the olfactory nerve, the administered insulinand/or pharmaceutical composition and/or components thereof may betransported through the tissue and travel along olfactory neurons intoareas of the CNS including but not limited to the brain stem,cerebellum, spinal cord, cerebrospinal fluid, olfactory bulb, andcortical and subcortical structures. Thus, an effective amount ofinsulin and/or pharmaceutical composition thereof, is delivered to thetarget CNS for protection of the brain of a subject at risk of injuryleading to TBI and/or treatment of TBI.

The blood-brain barrier is bypassed in the present invention byapplication of at least an effective amount of insulin and/orpharmaceutical composition(s) comprising insulin and/or composition(s)or compound(s) to the upper third of the nasal cavity of the patient,e.g., a mammal. The administered amount of the insulin and/orpharmaceutical composition thereof of the invention migrate from thenasal mucosa through foramina in the cribriform plate along theolfactory neural pathway and an effective amount is delivered directlyinto the CNS. Further, vasoconstrictors may be applied to the nasalcavity of the patient, either before or during the application of the atleast an effective amount of insulin and/or pharmaceuticalcomposition(s) thereof to the upper third of the patient's nasal cavity,to enhance the efficiency of delivery of the an effective amount ofinsulin to the patient's CNS and minimization of any potential systemicexposure of the administered insulin.

Administration to the nasal cavity employing a neural pathway can thusdeliver an effective amount of therapeutic agent(s), e.g., insulinand/or pharmaceutical compositions thereof to the lymphatic system,brain stem, cerebellum, spinal cord, and cortical and subcorticalstructures of the mammalian patient. The therapeutic agent(s), e.g.,insulin and/or pharmaceutical composition(s) thereof of the presentinvention alone may facilitate this movement into the CNS, i.e., brain,and/or spinal cord. Alternatively, a carrier may assist in the transportof the administered insulin and/or pharmaceutical composition of thepresent invention into and along the neural pathway. Administration ofthe insulin and/or pharmaceutical composition(s) thereof of the presentinvention to the upper third of the mammalian patient's nasal cavitythus enables bypassing of the blood-brain barrier through a transportsystem from the nasal mucosa and/or epithelium to the CNS, i.e., brainand spinal cord where an effective amount of the administered insulin isdelivered.

Various embodiments of the invention administer an at least an effectiveamount of insulin and/or pharmaceutical composition(s) thereof of thepresent invention to tissue innervated by the olfactory nerves. Suchnerve systems can provide a direct connection between the outsideenvironment and the brain, thus providing advantageous delivery of theagent(s) and/or compound(s) to the CNS, including brain, brain stem,and/or spinal cord. The administered insulin and/or pharmaceuticalcomposition(s) thereof of the present invention may be unable to crossor inefficiently cross the blood-brain barrier from the bloodstream intothe brain. Alternatively, for those agent(s) and/or composition(s) thatmay cross the blood-brain barrier, the present invention offers analternative treatment for those patients having a concurrent system,non-CNS disease or condition that contraindicates systemicadministration of the therapeutic agent(s) and/or compositions(s) neededwithin the CNS to treat a first CNS-related disease, condition ordisorder. Thus, the methods of the present invention allow for thedelivery of an effective amount of insulin and/or pharmaceuticalcomposition(s) thereof to the target CNS by way of the olfactory nerverather than through the circulatory system in order to facilitateprotection of the brain of a subject at risk of injury leading to TBIand/or treatment of TBI. Thus, this method of administration of at leastan effective amount of insulin to the upper third of the nasal cavityand delivery of the effective amount of insulin to the target CNS allowsfor the efficient and non-invasive delivery of an effective amount ofinsulin and/or pharmaceutical composition(s) thereof of the presentinvention to the CNS, brain, or spinal cord without systemic loss orexposure.

Alternative Pathways

Alternative non-systemic pathways to the olfactory nerve pathwaydiscussed above comprise pathways along other nerves that innervate thenasal cavity, e.g., the trigeminal pathway, well known to the skilledartisan.

Administration of Therapeutic Agent(s) and/or Pharmaceutical Compounds

Administering insulin according to the methods of the invention forprotection of the brain of a subject at risk of injury leading to TBIand/or treatment of TBI may include application of at least an effectiveamount of the therapeutic agent, i.e., insulin alone or formulating theat least an effective amount of insulin with at least an effectiveamount of one or more of the compounds described supra as pharmaceuticalcompositions and administering the pharmaceutical compositions to amammalian subject or host, including a human patient, intranasally tothe upper third of the nasal cavity. The therapeutic agent(s) and/othercomponents of the pharmaceutical composition thereof, e.g.,vasoconstrictor may be administered at one of a variety of dosessufficient to provide an effective amount at the desired point of actionin the CNS for the administered at least an effective amount of insulinand/or pharmaceutical composition component.

As noted, vasoconstrictor(s) may be delivered as pre-treatment,co-treatment and/or post-treatment with the therapeutic agent(s) and/orpharmaceutical composition, either alone or as a component of thepharmaceutical composition. Delivery of at least an effective amount ofinsulin in this manner results in delivery of an effective amount ofinsulin to the target CNS with maximum efficiency in the delivery ofinsulin, i.e., with minimal to no systemic exposure of insulin.

For application to the upper third of the nasal cavity as suspensions,aerosols, sprays or drops, the at least an effective amount of insulinand/or pharmaceutical composition(s) can be prepared according totechniques well known in the art of pharmaceutical formulation. Thecompositions can be prepared as suspensions of the agent(s) in solutionswhich may comprise salts such as saline, components such as phosphate,succinate or citrate buffers to maintain pH, osmoregulatory and osmoticagents such as taurine, and suitable preservatives, absorption promotersto enhance bioavailability, fluorocarbons or other solubilizing ordispersing agents known in the art. The means of applying apharmaceutical composition intranasally to the upper third of the nasalcavity may be in a variety of forms such as a powder, spray, gel or nosedrops.

Other forms of compositions for administration of the at least aneffective amount of insulin and/or pharmaceutical compositions orelements thereof include a suspension of a particulate, such as anemulsion, a liposome, or in a sustained-release form to prolong thepresence of the pharmaceutically active agent in an individual. Thepowder or granular forms of the pharmaceutical composition may becombined with a solution and with a diluting, dispersing orsurface-active agent. Additional compositions for administration includea bioadhesive to retain the agent at the site of administration at theupper third of the nasal cavity, for example a spray, paint, or swabapplied to the mucosa. A bioadhesive can refer to hydrophilic polymers,natural or synthetic, which, by the hydrophilic designation, can beeither water soluble or swellable and which are compatible with thepharmaceutical composition. Such adhesives function for adhering theformulations to the mucosal tissues of the upper third of the nasalcavity. Such adhesives can include, but are not limited to,hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethylcellulose, ethylcellulose, carboxymethyl cellulose, dextran, gaurgum, polyvinyl pyrrolidone, pectins, starches, gelatin, casein, acrylicacid polymers, polymers of acrylic acid esters, acrylic acid copolymers,vinyl polymers, vinyl copolymers, polymers of vinyl alcohols, alkoxypolymers, polyethylene oxide polymers, polyethers, and combinationsthereof. The composition can also be in the form of lyophilized powder,which can be converted into solution, suspension, or emulsion beforeadministration. The pharmaceutical composition is preferably sterilizedby membrane filtration and is stored in unit-dose or multi-dosecontainers such as sealed vials or ampoules.

The pharmaceutical composition may be formulated in a sustained-releaseform to prolong the presence of the active therapeutic agent(s) in thetreated individual. Many methods of preparation of a sustained-releaseformulation are known in the art and are disclosed in Remington'sPharmaceutical Sciences. Generally, the therapeutic agent(s),pharmaceutical composition and/or components of the pharmaceuticalcomposition, i.e., vasoconstrictor may be entrapped in semi-permeablematrices of solid hydrophobic polymers. The matrices can be shaped intofilms or microcapsules. Matrices can include, but are not limited to,polyesters, co-polymers of L-glutamic acid and gamma ethyl-L-glutamate,polylactides, polylactate polyglycolate, hydrogels, non-degradableethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers,and alginic acid suspensions. Suitable microcapsules can also includehydroxymethylcellulose or gelatin and poly-methyl methacrylate.Microemulsions or colloidal drug delivery systems such as liposomes andalbumin microspheres can also be used.

Delivery Systems

The therapeutic agent, i.e., insulin, and/or a pharmaceuticalcomposition comprising at least an effective dose of insulin and/orcomponents of the pharmaceutical composition of the present inventionmay further be dispensed and applied to the upper third of the nasalcavity as a powdered or liquid nasal spray, suspension, nose drops, agel, film or ointment, through a tube or catheter, by syringe, bypacktail, by pledget (a small flat absorbent pad), by nasal tampon or bysubmucosal infusion. In some aspects of the present invention, themethods comprise administering to an individual the at least aneffective dose of insulin and/or a pharmaceutical composition thereof tothe upper third of the nasal cavity by way of a delivery device. Nasaldrug delivery can be carried out using devices including, but notlimited to, unit dose containers, pump sprays, droppers, squeezebottles, airless and preservative-free sprays, nebulizers (devices usedto change liquid medication to an aerosol particulate form), metereddose inhalers, and pressurized metered dose inhalers. In some aspects,an accurate effective dosage amount is contained within a bioadhesivepatch that is placed directly within and on the upper third of a nasalcavity.

At least an effective dose of insulin and/or a pharmaceuticalcomposition comprising at least an effective dose of insulin and/orcomponents of the therapeutic composition of the present invention maybe conveniently delivered to the upper third of the nasal cavity in theform of an aerosol spray using a pressurized pack or a nebulizer and asuitable propellant including, but not limited to,dichlorodifluoromethane, trichlorofluoromethane,dichlorotetrafluoroethane, hydrocarbons, compressed air, nitrogen orcarbon dioxide. An aerosol system requires the propellant to be inerttowards the therapeutic agent(s) and/or pharmaceutical composition aswill be readily recognized by the skilled artisan. In the case of apressurized aerosol, the dosage unit may be controlled by providing avalve to deliver an accurately metered amount.

The means to deliver the at least an effective amount of insulin orpharmaceutical composition comprising the at least an effective amountof insulin and/or components of the pharmaceutical composition of thepresent invention to the upper third of the nasal cavity as a powder maybe in a form such as microspheres delivered by a nasal insufflatordevice (a device to blow a gas, powder, or vapor into a cavity of thebody) or pressurized aerosol canister. The insufflator produces a finelydivided cloud of the dry powder or microspheres. The insufflator may beprovided with means to ensure administration of a substantially meteredamount of the pharmaceutical composition. The powder or microspheresshould be administered in a dry, air-dispensable form. The powder ormicrospheres may be used directly with an insufflator which is providedwith a bottle or container for the powder or microspheres. Alternativelythe powder or microspheres may be filled into a capsule such as agelatin capsule, or other single dose device adapted for nasaladministration. The insufflator can have means such as a needle to breakopen the capsule or other device to provide holes through which jets ofthe powdery composition can be delivered to the upper third of the nasalcavity.

Intermittent and Cyclic Dosing

In various embodiments of the invention, therapeutic agent, i.e.,insulin, and/or a pharmaceutical composition comprising at least aneffective amount of insulin and/or the components of the pharmaceuticalcomposition may be administered as a single and one-time dose, oralternatively the at least an effective amount of insulin and/or thecomponents of the pharmaceutical composition may be administered morethan once and intermittently. By “intermittent administration” isintended administration of at least an effective amount of insulinand/or the components of the pharmaceutical composition, followed by atime period of discontinuance, which is then followed by anotheradministration of the at least effective amount, and so forth.Administration of the at least an effective amount of insulin and/or thecomponents of the pharmaceutical composition may be achieved in acontinuous manner, as for example with a sustained-release formulation,or it may be achieved according to a desired daily dosage regimen, asfor example with one, two, three, or more administrations per day. By“time period of discontinuance” is intended a discontinuing of thecontinuous sustained-released or daily administration of the insulinand/or the components of the pharmaceutical composition. The time periodof discontinuance may be longer or shorter than the period of continuoussustained-release or daily administration. During the time period ofdiscontinuance, the concentration(s) of insulin and/or the components ofthe pharmaceutical composition level in the relevant tissue issubstantially below the maximum level obtained during the treatment. Thepreferred length of the discontinuance period depends on theconcentration of the effective dose and the form of therapeutic agent(s)and/or the components of the pharmaceutical composition used. Thediscontinuance period can be at least 2 days, preferably is at least 4days, more preferably is at least 1 week and generally does not exceed aperiod of 4 weeks. When a sustained-release formulation is used, thediscontinuance period must be extended to account for the greaterresidence time of the at least one therapeutic agent at the site ofinjury. Alternatively, the frequency of administration of the effectivedose of the sustained-release formulation can be decreased accordingly.An intermittent schedule of administration of insulin and/or thecomponents of the pharmaceutical composition may continue until thedesired therapeutic effect, and ultimately treatment of the disease ordisorder is achieved.

In yet another embodiment, intermittent administration of the at leastan effective amount(s) of insulin and/or the components of thepharmaceutical composition is cyclic. By “cyclic” is intendedintermittent administration accompanied by breaks in the administration,with cycles ranging from about 1 month to about 2, 3, 4, 5, or 6 months.For example, the administration schedule might be intermittentadministration of the at least an effective dose of insulin and/or thecomponents of the pharmaceutical composition, wherein a singleshort-term dose is given once per week for 4 weeks, followed by a breakin intermittent administration for a period of 3 months, followed byintermittent administration by administration of a single short-termdose given once per week for 4 weeks, followed by a break inintermittent administration for a period of 3 months, and so forth. Asanother example, a single short-term dose may be given once per week for2 weeks, followed by a break in intermittent administration for a periodof 1 month, followed by a single short-term dose given once per week for2 weeks, followed by a break in intermittent administration for a periodof 1 month, and so forth. A cyclic intermittent schedule ofadministration of insulin and/or the components of the pharmaceuticalcomposition to a subject may continue until the desired therapeuticeffect, and ultimately treatment of the disorder or disease is achieved.

Working Example

In a reduction to practice of one embodiment of the present invention, aModerate Controlled Cortical Impact Injury Model, developed for use inestablishing a Traumatic Brain Injury (TBI) model was employed. In thisstudy, adult male Sprague Dawley rats were subjected to a controlledcortical impact as that procedure is described in “A mouse model ofsensorimotor controlled cortical impact: characterization usinglongitudinal magnetic resonance imaging, behavioral assessments andhistology”. Onyszchuk G, Al-Hafez B, He Y Y, Bilgen M, Berman N E,Brooks W M. J Neurosci Methods. 2007 Mar. 15; 160(2):187-96. Onyszchuk,G., et al., J. Neurosci. Methods, 2007, 160(2): p. 187-196, the contentsof which are hereby incorporated by reference.

Procedure

Following the controlled injury using the TBI model described above, theinjured rats received either saline or insulin under anesthesia byisoflurane. A first dose of either saline (saline rats) or insulin(insulin rats) was delivered 4 hours post-injury to the upper third ofthe nasal cavity as described above in connection with the presentinvention. Thereafter, doses of saline or insulin were administered oncea day for 7 to 14 days to the upper third of the nasal cavity. Motorfunction was evaluated in the saline rats and with the insulin rats. Inaddition, immunohistochemistry and Western Blot analyses were performedwith a focus on inflammatory cells, microglia, and neuronal survival.

Results

Blood was taken from the tail vein of a small cohort of rats (n=3 pertreatment group) immediately prior to injury, 4 hours afterinjury/immediately before treatment and 3 hours after treatment. Theresults indicate no significant difference in blood glucose between thetwo groups, shown in FIG. 5. Consequently, the administration of insulinto the upper third of the nasal passage does not significantly affectthe patient's blood glucose.

In addition, both the saline rats and the insulin rats were weighed ondays 1, 7, 14 and 21 post-injury. The results indicate no significantdifference in weight between the two groups. Consequently, theadministration of insulin to the upper third of the nasal passage doesnot significantly affect the patient's weight.

Motor function tests consisting of a beam walk and a peg walk, bothtests well-established measures of functional deficit and recovery inpreclinical TBI research, were also given to the saline rats and theinsulin rats on days 1 and 7 post-injury. The results for the beam walk,shown in FIG. 1, indicate a significant decrease in time for the insulinrats to cross the beam as compared with day 1 baseline results and ascompared with the saline (vehicle) rats performance on day 7.

The peg walk results illustrated in FIG. 2 indicate a positive trendtowards improved motor function in the insulin rat group from baselineresults from day 1 as well as when compared with saline (vehicle) ratson day 7. Thus, intranasal insulin, administered according to thepresent invention to the upper third of the nasal cavity in subjectswith TBI results in improved motor function in those subjects.

Blood glucose levels were also tested following intranasal insulindelivery. FIG. 5 illustrates a lack of change in blood glucose afterintranasal insulin delivery (injury− CCI−completed at time=1 h; insulinor saline administered at time=4 h; final blood draw at time=7 h).

Cognitive function was also tested in saline (vehicle) and insulintreated rats on days 11-14 post-injury, using the well-known andwell-justified Morris water maze task. Memory retention was assessedusing the probe trial portion of the task, and showed thatinsulin-treated rats had a significant increase in the number of crossesof the target island region in comparison to saline (vehicle) treatedrats, where they had been previously trained to exit the maze, as shownin FIG. 6. In addition, search strategy, which indicates method ofsearching the maze for the exit island, shown in FIG. 7, demonstratesthat saline (vehicle) treated rats utilized significantly less targetedsearch methods (looping) than insulin rats.

In addition to the above motor and cognitive function tests, the effectof insulin administered to the upper third of the nasal cavity in theinsulin rat group as compared with the saline rat group was alsoevaluated by using an immunohistochemical marker of neurons,specifically NeuN, to examine the effect of the insulin on neurons inthe hippocampus post-injury after sacrifice on day 8. FIGS. 8a and 9bare photographs that indicate, following a quantitative assessmentaccording to well-known methods, an improved neuronal viability in thehippocampus of the intranasal rats as compared with the saline rats.FIG. 8a illustrates neuronal viability in the saline rat hippocampus.FIG. 8b illustrates an improved neuronal viability in the insulin rathippocampus, as illustrated by the brighter and more robust neuronalpresence as compared with the saline rat of FIG. 8 a.

Finally, the effect of insulin administered as in the Working Example onmicroglia was evaluated post-injury and following sacrifice on day 8 forthe saline rats and the insulin rats. Microglia are the macrophages ofthe brain, with two dominant phenotypes: M1 and M2.

M1 microglia are classically activated pro-inflammatory cells. M1microglia are useful in the initial healing process, but persistentactivation results in neuronal cell death due to production of reactiveoxygen species. M2 microglia are anti-inflammatory, pro-healingmacrophages.

The Working Example results, illustrated in FIGS. 3 and 4 indicate asignificant increase in M2 microglia, characterized by expression ofCD206, in the intranasal rats as compared with the intranasal salinerats as shown in FIG. 3. There was no significant increase in expressionof M1 microglia markers, characterized by expression of CD86 and asillustrated in FIG. 4. This indicates, inter alia, that the insulinregimen according to the present invention and as used in the WorkingExample is pushing the microglia toward the M2 anti-inflammatoryphenotype. Thus, subjects with TBI that are treated with insulinadministered to the upper third of the subject's nasal cavity experiencean increase in activation of anti-inflammatory cells, specifically M2microglia cells which, in turn promote healing of the damaged cells inthe subject with TBI, or protect against damage to the brain of asubject at risk of injury to the brain leading to TBI.

Further, inflammation is a major, and damaging, component ofneurodegenerative central nervous system disorders, including but notlimited to Alzheimer's disease, Parkinson's disease, ALS, Huntington'sdisease, to name a few. As a result, the discovery that intranasalinsulin increases the M2 anti-inflammatory microglia phenotype in thebrain of a patient experiencing neuroinflammation in the brain as aresult of brain injury or other neurodegenerative disorder, conditionand/or disease is applicable and useful to protect, prevent and/or treatsuch inflammation.

Conclusion

The Working Example indicates that insulin administered to the upperthird of the patient's nasal cavity, increases neuronal viability in thehippocampus, increased the formation of anti-inflammatory M2 microgliawhich promote healing, and increased motor and cognitive functionalrecovery after Traumatic Brain Injury (TBI).

In addition, the results of the Working Example indicate that insulindelivered to the brain of patients with brain injury or otherneurodegenerative disorder involving inflammation of the brain can beused to reduce the associated inflammation by increasing production ofthe M2 anti-inflammatory phenotype in the patient's brain. Certainly,neurodegenerative disorders such as Alzheimer's disease, Parkinson'sdisease, Huntington's disease, ALS involve inflammation of the brain andare, therefore, amenable to treatment using the present invention. Inaddition, patients at risk of developing a neurodegenerative conditionand/or disease leading to neuroinflammation may be identified and theneuroinflammation prevented, or protected against.

The invention has been described with reference to various specific andpreferred embodiments and techniques. However, it should be understoodthat many variations and modifications may be made while remainingwithin the spirit and scope of the invention.

We claim:
 1. A method for treating traumatic brain injury (TBI) in apatient, wherein the patient's risk of developing Alzheimer's disease isincreased by the TBI, comprising: administering a therapeutic agentconsisting of at least an effective amount of insulin to the upper thirdof the nasal cavity of the patient, and thereby enabling at least aneffective amount of insulin to directly access the patient's centralnervous system by bypassing the blood-brain barrier; and treating thepatient's TBI, and protecting against the patient developing Alzheimer'sdisease as a result of the TBI by protecting the patient's brain frominflammation and reducing inflammation in the patient's brain byincreasing the expression of anti-inflammatory M2 microglia cells in thepatient's brain.
 2. The method of claim 1, further comprisingadministering the insulin to a tissue innervated by the olfactory nerve,wherein the administered insulin bypasses the blood-brain barrier toaccess the patient's central nervous system to treat the TBI.
 3. Themethod of claim 2, further comprising the administered insulin bypassingthe blood-brain barrier by migrating along a neural pathway into thepatient's central nervous system to treat the patient's TBI.
 4. Themethod of claim 1, wherein the administered insulin comprises a non-zincinsulin.
 5. The method of claim 2, further comprising pretreating thepatient's nasal cavity with an effective amount of at least onevasoconstrictor before administering the insulin to the upper third ofthe patient's nasal cavity.
 6. The method of claim 1, wherein the atleast an effective amount of insulin is in the range of 1×10⁻⁷ to 0.1mg/kg, with reference to the patient's body weight.
 7. The method ofclaim 1, wherein a more preferred dosage range for the at least aneffective amount of insulin is in the range of 1×10⁻⁴ to 0.1 mg/kg, withreference to the patient's body weight.
 8. The method of claim 1,wherein the concentration of insulin in the brain of the patient after asingle dose is in the range of 1×10⁻¹³ to 1×10⁻⁹ molar.
 9. A method fortreating traumatic brain injury (TBI) in a patient, wherein thepatient's risk of developing Alzheimer's disease is increased by theTBI, comprising: administering a therapeutic agent consisting of atleast an effective amount of insulin to the upper third of the nasalcavity of the patient, and thereby enabling at least an effective amountof insulin to directly access the patient's central nervous system bybypassing the bloodbrain barrier; and treating the patient's TBI, andprotecting against the patient developing Alzheimer's disease as aresult of the TBI.
 10. The method of claim 9, further comprisingadministering the insulin to a tissue innervated by the olfactory nerve,wherein the administered insulin bypasses the blood-brain barrier toaccess the patient's central nervous system to treat the TBI.
 11. Themethod of claim 9, wherein the administered insulin comprises a non-zincinsulin.
 12. The method of claim 9, wherein the at least an effectiveamount of insulin is in the range of 1×10⁻⁷ to 0.1 mg/kg, with referenceto the patient's body weight.
 13. The method of claim 9, wherein a morepreferred dosage range for the at least an effective amount of insulinis in the range of 1×10⁻⁴ to 0.1 mg/kg, with reference to the patient'sbody weight.
 14. The method of claim 9, wherein the concentration ofinsulin in the brain of the patient after a single dose is in the rangeof 1×10⁻¹³ to 1×10⁻⁹ molar.